Graduation date: 1957

Graduation date: 1957

No description available.

No description available.

The phenolic extractives from western hemlock wood (Tsuga heterophylla (Raf.) Sar.) have been examined. The total extractive content of the wood amounted to 1.5% of the dry weight. A leucoanthocyanidin and two lignans, conidendrin and hydroxymatairesinol, were isolated from the phenolic fraction by precipitation of a methanol solution into peroxide-free ether followed by separation on silicic acid-calcium sulphate chromatobars. The pigment produced by acid treatment of the isolated leucoanthocyanidin was shown by spectral studies and alkaline degradation to be a mixture of cyanidin and an unidentified anthocyanidin. The two anthocyanidins had identical Rf values in different solvents and similar ultra-violet spectra in ethanol-hydrochloric acid solution but the shift of the absorption maxima caused by addition of aluminium chloride was negligible in the case of the unknown compound and amounted to 30 mµ for cyanidin. Similar separations of the absorption maxima after complexing with aluminium ion were observed with the 3-methyl and 3-isopropyl ethers of the two anthocyanidins. The alkaline degradation products from the leucoanthocyanidin contained protocatechuic acid but no phloroglucinol. Degradation products of phloroglucinol, however, were present in the reaction mixture. These results suggested that the leucoanthocyanidin occurred in the wood in dimeric form and that alkaline degradation of this structure produced a symmetrical hexahydroxyhenzophenone derivative which split up directly into fragments identical to those obtained from phloroglucinol under the same conditions. New information on the structure of hydroxymatairesinol was obtained by comparison of the infrared spectra of the fully acetylated hydroxymatairesinol with that of the reduced compound and by neutral potassium permanganate oxidation of trimethylhydroxymatairesinol. The results obtained were in good agreement with only one of the two structures previously proposed for hydroxymatairesinol by other workers. The NMR spectra of hydroxymatairesinol and structurally related compounds were compared, but the interpretation of the spectrum of hydroxymatairesinol proved to be difficult because broad, incompletely resolved lines were obtained due to the complexity and asymmetry of the molecule. / Science, Faculty of / Chemistry, Department of / Graduate

It was the purpose of this study to compare pulps prepared from normal, sound wood with those prepared from juvenile wood, compression wood, tension wood and decayed wood with regard to their apparent degree of crystallinity. The crystallinity index and crystallinity ratio of the pulps prepared from these woods were determined by two different X-ray methods. In method A, the principle of the Debye-Scherrer powder technique was applied and the crystallinity index of the pulp was evaluated from the 002 peak of the X-ray diffraction pattern. In method B a Geiger-counter X-ray spectrometer was used and the crystallinity ratio of holocellulose was evaluated from the (101 +101¯) combination peak. It was found that the apparent crystallinity of wood pulp and holocellulose prepared from normal western hemlock wood increased significantly through successive growth rings from the pith to about 15 years, after which it reached a more or less constant value. The crystallinity of wood pulp and holocellulose of summerwood was significantly higher than that of springwood. The crystallinity of wood pulp and holocellulose of compression wood from Douglas fir was considerably lower than that of normal wood, whereas the crystallinity of tension wood from cottonwood was significantly higher than that of normal wood. The crystallinity of cottonwood and Douglas fir holocellulose increased significantly during the incipient stage of decay. The rate of increase in crystallinity was very rapid during the incipient stage of decay represented by a six percent weight loss, but became very slow and showed an almost constant value thereafter. The relative value of crystallinity after decay depends mainly on the initial crystallinity rather than the history of decay. / Forestry, Faculty of / Graduate

[Part I] Desoxytigogenin was prepared by oxidation followed by Wolff-Kishner reduction of tigogenin. A number of methods were employed to open the side chain of desoxytigogenin to the corresponding dihydrodesoxytigogenin. Oxidation of dihydrodes-oxytigogenin yielded the corresponding C₂₆ aldehyde, which was isolated in pure form and characterised unambiguously. Bromination studies under varying conditions have been made on this aldehyde but the results have not been completed as yet. [Part II] The ground material from the bark of Diphlorynchus Mossambicensis was extracted with methanol, and methanol soluble concentrate was obtained. In addition a green gummy material, sparingly soluble in methanol, was obtained. The methanol concentrate was separated into acid, basic and neutral fractions and preliminary chemical investigations were made on these fractions. Two crystalline substances of empirical formulas C₃₀₋₃₅H₄₄₋₅₄O₂ and C₃₇₋₃₈H₅₂₋₅₆O₂ have been isolated, separated and purified from the green gummy material. Spectral and analytical data have been collected and a few chemical reactions have been made on these two compounds. / Science, Faculty of / Chemistry, Department of / Graduate

Because of difficulty experienced with visual observation of bleached, unstained softwood tracheids, a study was initiated to determine the best microscopic system, for observation of this type of material. A comparison was made between bright-field, dark-field, polarising, phase, electron, fluorescence and interference microscopic systems. In addition, the optical characteristics of each type of microscope were studied to determine the reasons for the differences in visual results. The study was expanded to include an evaluation of the interference microscope and its use in measuring refractive index of bleached wood pulp. The interference microscope was found to give visual images superior to those obtained with any of the other systems examined and thus constitutes an important, contribution to the practice of microscopy. Inconclusive results were obtained in the evaluation of the system of measurement of refractive index by means of the interference microscope. / Forestry, Faculty of / Graduate

A method is described for the preparation of an induced xylanase from Chaetomlum globosum. This soil micro-organism was first grown in synthetic liquid media containing xylan as the sole carbon source. After incubation at room temperature for a suitable time, the mycella were harvested, centrifuged and exposed to high frequency vibrations which ruptured the cell walls. The resulting clear enzyme solution was shown to be capable of hydrolysing xylan from wheat straw. The main end product of hydrolysis detected by means of paper chromatography was xylose. The action of this induced enzyme preparation on wood cellulose was studied. A considerable fraction of the xylan was removed without significantly changing the mannose or glucose content. In connection with the enzyme studies, a method is given for the quantitative determination of polysaccharides in wood-cellulose preparations. Direct photometric analyses of the wood hydrolysate spots on paper chromatograms were made with an adapted Beckman spectrophotometer. An analysis of selected commercial pulps is given together with a comparison of the method with conventional pentosan analyses. / Medicine, Faculty of / Biochemistry and Molecular Biology, Department of / Graduate

The hemicellulose isolated from apple wood (var. Golden Transparent) by alkaline extraction has been shown to contain a 4-0-methylglucuronoxylan. Hydrolysis of the hemicellulose yielded neutral sugars and uronic acids. Paper chromatographic examination of the neutral sugars showed D-xylose to be the major component with small amounts of other sugars corresponding to rhamnose, arabinose and galactose also being present. Two other sugars with Rf values greater than that of xylose were found but the identity of these components has not been established. An aldobiouronic acid was isolated and characterized as the crystalline acetate of 2-0-(4-0-methyl-⍺-D-glucopyranosyluronic acid)-D-xylose. In order to determine the mode of union of the component sugars the polysaccharide was methylated and then hydrolyzed to give 2,3,4-tri-O-methyl-D-xylose, 2,3 di-O-methy1-D-xylose, 2-0-(2,3-di-O-methyl-D-xylopyranosyl)-2,3-di-O-methyl-D-xylose, a dimethylated lyxose, 2-0- and 3-0-methyl-D-xylose, 2-0-(2,3,4-tri-O-methyl-D-glucopyranosyluronic acid)-D-xylose, and probably a trimethylated rhamnose. (The dimethylated lyxose isolated is not an integral constituent of the native polysaccharide since no lyxose was obtained in the acid hydrolyzate. It is thought to arise by epimerization of 2,3-di-0-methyl-D-xylose.) Quantitative analysis of the methylated hemicellulose has shown the tri-, di- and monomethyl pentose and 2,3,4-tri-O-methyl-D- ⍺- glucuronic acid to be present in the mole ratios of 1:97:21:19, respectively. The methyl ester of the methylated aldobiouronic acid was reduced with lithium aluminum hydride and the resulting neutral disaccharide hydrolyzed. The cleavage products were identified as 3-0-methyl-D-xylose and 2,3,4-tri-0-methyl -D-glucose indicating the uronic acid portion of the molecule to be linked through its reducing end to position 2 of a xylose moiety. Results obtained in this work show that the carbohydrate polymer isolated from apple wood consists of a backbone of approximately 119 anhydro-D-xylopyranose linked by 1,4-β-glycosidic bonds. The side chains are composed of single units of 4-0-methyl-D-glucuronic acid which occur at every sixth xylose residue. A rhamnose unit may perhaps be present as a side chain too, although it is not known whether this sugar is an integral constituent of the glucuronoxylan. The general features of the hemicellulose are very similar to glucuronoxylans isolated from other hardwoods and especially resemble white elm and cherry wood in its structure and high uronic acid content. We are grateful to Dr. C. T. Bishop who presented this work at the 43rd conference of The Chemical Institute of Canada, Ottawa, June I960. / Science, Faculty of / Chemistry, Department of / Graduate